Chloroform
Connecticut Water Company - Amston Lake Division
Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Read More.
In addition to tap water disinfection, chloroform pollution in the environment also comes from industrial discharges from pulp and paper mills, and from urban wastewater effluent. Human studies show that chloroform damages the kidneys, liver and central nervous system. In animals, chloroform causes infertility, birth defects and cancer.
Samples
Samples exceeding legal limit (MCL)
Samples exceeding
health guidelines
Testing results - average by year
| Year | Average result | Samples taken | Detections | Range of results |
|---|---|---|---|---|
| 2018 | 1.02 ppb | 5 | 1 | ND - 5.10 ppb |
| 2019 | 1.65 ppb | 4 | 2 | ND - 3.90 ppb |
| 2020 | 2.85 ppb | 2 | 1 | ND - 5.70 ppb |
| 2021 | 0.250 ppb | 2 | 1 | ND - 0.500 ppb |
| 2022 | 2.10 ppb | 3 | 2 | ND - 4.40 ppb |
| 2023 | 2.05 ppb | 2 | 1 | ND - 4.10 ppb |
ppb = parts per billion
State, National, and Health Guidelines for Drinking Water
EWG Health Guideline: 0.4 ppb
The EWG Health Guideline of 0.4 ppb for chloroform was based on the California Office of Environmental Health Hazard Assessment's public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer and harm to fetal growth and development.
ppb = parts per billion
All test results
| Date | Lab ID | Result |
|---|---|---|
| 2018-01-19 | BZ75818VOC1 | ND |
| 2018-04-09 | CA16127VOC1 | ND |
| 2018-07-23 | CA95518 | ND |
| 2018-08-13 | CB09779 | 5.10 ppb |
| 2018-11-15 | VOC1 200512952 | ND |
| 2019-02-19 | VOC1 200522111 | 2.70 ppb |
| 2019-02-19 | VOC1 200522112 | ND |
| 2019-04-08 | VOC1 200527488 | ND |
| 2019-08-26 | DBP 200546238 | 3.90 ppb |
| 2020-08-14 | DBP 200586774 | 5.70 ppb |
| 2020-09-21 | VOC1 200590982 | ND |
| 2021-01-06 | VOC1 200602955 | ND |
| 2021-08-16 | DBP 200628739 | 0.500 ppb |
| 2022-08-12 | CM04227 | 4.40 ppb |
| 2022-09-23 | CM40531 | 1.90 ppb |
| 2022-09-23 | CM40528 | ND |
| 2023-08-16 | CO76119 | 4.10 ppb |
| 2023-10-24 | CP33072 | ND |